Internal combustion engines are used in various mobile and stationary machines to generate power by the combustion of a fuel such as diesel fuel. In many applications, it is desirable to reduce the emission of particulate matter (e.g., soot) and/or nitrogen oxides (NOX) produced by the operation of the engine. With this goal in mind, exhaust systems of internal combustion engines may include one or more devices that treat exhaust prior to releasing the exhaust into the environment. Such devices, which may be referred to as aftertreatment devices, may include particulate traps that capture particulate matter, and/or catalysts that react with exhaust (e.g., by catalyzing a reaction) to reduce NOX emissions.
Under certain conditions, the aftertreatment device may underperform and/or suffer a marked decline in performance. For example, when an ambient temperature or the temperature of the engine is low, an aftertreatment device including a catalyst may perform inefficiently. In such cases, exhaust emissions may fall short of emissions guidelines until a temperature of the aftertreatment device reaches a minimum temperature. Additionally, operating an internal combustion engine in an idle load level for extended periods of time may result in hydrocarbon buildup that negatively affects performance. In addition to hydrocarbon buildup, sulfur buildup may even largely deactivate aftertreatment devices such as diesel particulate filters. In order to restore the performance of the aftertreatment device, a regeneration may be performed. Regeneration may include raising the temperature of the aftertreatment device to a desired level for a period of time to remove hydrocarbons and/or sulfur.
An exemplary apparatus including an engine load module is disclosed in International Publication No. WO 2015/035133 A1 (“the '133 publication”) to Mehrotra et al. The apparatus described in the '133 publication may generate a request to deactivate a cylinder to lead to an increase in combustion temperatures and therefore, an increase in exhaust gas temperatures. While the cylinder deactivation described in the '133 publication may be useful to raise exhaust gas temperatures in some situations, the apparatus described in the '133 publication may not be useful in other situations, for example where cylinder deactivation does not raise exhaust gas temperatures to a level capable of sufficiently warming or regenerating an exhaust aftertreatment device.
The disclosed method and system may solve one or more of the problems set forth above and/or other problems in the art. The scope of the current disclosure, however, is defined by the attached claims, and not by the ability to solve any specific problem.